Die-casting machine



Aug. 17 1926.

G. W- BUNGAY DIE CASTING MACHINE 3 Sheets-Sheet 1 ATTORNEYS Filed Sept. 27, 1924 G. w. BUNGAY DIE CASTING- MACHINE Sept. 27 1924 3 Sheets-Sheet 2 INVENTR ATTORNEYS Aug. 17 1926.

G.'w. BUNGAY DIE CASTING MACHINE Filed Se t; 27,

3 Sheets-Sheet 5 R O T N E ATTORNEYS Patented Aug. 17, 1926.

UNITED STATES PATENT OFFICE.

J'EORGE W. BUNGAY, OF PLAINFIELD, NEW JERSEY, ASSIGNOR TO ALUMINUM IDIE- CASTING CORPORATION, OF GARWOOD, NEW JERSEY, A CORPORATION OF NEW JERSEY.

DIE-CASTING MACHINE.

Application filed September 27, 1924. Serial No. 740,180.

This invention relates to die casting machines employing die sections, atleast one of which is adapted to be moved toward or away from the other through the instrumentality of a suitable die cl-o's'iing means comprising, for example, a cylinder into which steam is admitted to operate a piston which, in turn, through suitable mechanism is adapted to eifect the desired relative movement between the die sections.

An important object of the invention is to provide an improved, simple and reliable means adapted to be brought into operation subsequently to the closing of the die to lock the die closing means against return movement, under the influence of pressure set up within the die upon the introduction of the molten metal thereinto, and thus retain the adjacent faces of the die sections in an intimate engagement with each other during the casting operation.

Other objects and certain advantages of the invention will become apparent from the following description when taken in conmotion with the accompanying drawings in which Figure 1 is a side elevation of a machine embodying my invention;

Figure 2 is a plan view of the machine;

Figure 3 is an end elevation of the machine as viewed from the right in Fig. 1.

In the drawings wherein for the purpose of illustration is shown what I at present consider the preferred form of my invention, the numeral 5 indicates a frame struc- Lure at one end of which is located a receptacle 6 adapted to retain molten metal used in the casting operation. Within receptacle 6 there is arranged a nozzle 7 which is so supported by-means of bearings 8 carried by the frame 5 that the open or exit end 9 of the nozzle may be submerged beneath the level of the molten metal to fill the nozzle.

By suitable fluid pressure, the molten metal may be discharged from the nozzle 7 when the same is moved to the position shown in Fig. 1, in which position the nozzle is adapted to receive upon its exit end a die indicated as a whole by the numeral 10. This die comprises sections 11 and 12, the former of which is connected to a frame 13, wherethe latter is connected to a movable head 11 so mounted upon the frame 13 as to move imh respect thereto and thereby force the section 12 into intimate r 'igag ment through an exhaust pipe 18..

with the Section 11 and at the same time clamp the die 10 in its entirety upon the exit end of the nozzle 7. The head 14 which is so mounted upon the ,frame 13 as to slide with respect thereto, is rigidly connected to a piston rod 15 secured to a piston 16 adapted to reciprocate within the pressure cylinder 17 which is suitably supported with respect to the frame 5. The piston 16 is adapted to be moved within the cylinder 17 under the influence of steam entering the cylinder through the pipes 18 .and 19, which in turn. are adapted to be alternately placed in communication with a common supply pipe 17' through the instrumentality. of a suitable valve 20 as will be readily understood. Exhaust of steam from the cylinder 17 to permit the desired operation ofthe piston 16 is provided for by reason ofthe fact that the pipes 17 and 18 are, by means of the valve 20, alternately open to the atmosphere That is -to say, when the pipe 17 is placed in communication with one end of the cylinder 17 through the pipe 19 the opposite end of the cylinder is at the same time opened to'the atmosphere through the pipes 18 and 18, and on, the other hand, when steam is admitvted, through the pipes 17' and 18, to the rear end of the cylinder, exhaust from the opposite end of the cylinder is permitted to escape through the pipes 19and 18. The piston rod 15 is of such a length as to project an appreciable distance through the cylinder 17 when the head 14 is retracted, as shown in Fig. 2. At the rear of the cylinder 17, there is arranged a cam guide 21 having an opening 22 formed therein through which the piston 15 is adapted to operate. This guide carries a vertically disposed cam 23, the cam face of which is slightly beveled to conform to the beveled end of the piston 15. To the lower end of the cam 23 is connected a piston rod 24 carrying a piston 25 adapted to operate within a pressure cylinder 26. The piston 25 is adapted to be moved within the cylinder 26 by hydraulic pressure admitted to and exhausted from opposite ends of the cylinder alternately through pipes 27 and 28. Intermediate the ydraulic pressure supply, not shown, and the cylinder 26, there is arranged a valve 29 for controlling the ingress and egress of fluid pressure to the cylinder 26. This valve, when positioned as shown, provides for the entrance of pressure into the upper end of the cylinder through the pipes 27 and 30, and at the same time permits the escape of exhaustfrom the. opposite end of the cylinder through the pipes 28 and 31. When it is desired to admit pressure into the lower end of the cylinder 26, the valve 29 is'so rotated as to establish communication between the pipes 28 and 30 whereupon the pipes 27 and 31 are simultaneously connected to provide for the escape of exhaust from the opposite end of the cylinder.

In operation, steam is admitted to the rear end of the cylinder 17 as the result of proper manipulation of the valve 20 whereupon the piston 15 together with the head 14 is so moved as to cause the die section 12 to intimately engage the section 11 and lock the die 10 securely upon the exit end of the nozzle 7. After the piston 15 has been so moved as to clamp the die 10 upon the nozzle 7, fluid pressure is admitted into the lower end of the cylinder 26 thus forcing the cam 23 upwardly within the guide 21. As the 'cam 23 moves upwardly, its inclined face intimately engages the inclined face of the piston rod 15 and thus, as the result of the co-operation between the cam 23 and the piston rod 15, the die section 12 is urged into intimate face engagement with the section 11 and the piston 16 is locked against return movement under the influence of pressure set up within the die 10 upon the introduction of molten metal thereinto. After the casting operation has been carried out, fluid pressure is admitted into the upper end of. the cylinder 26, thus so moving the cam 23 downwardly within the guide 21 as to permit the piston 15 to return as the result of introducing steam pressure into the forward end of the cylinder upon proper manipulation of the valve 20.

By employing a steam operated piston, through the movement of which the dies are closed and opened, the machine may be operated at a high rate of speed as compared with the speed ofa machine employmg hydraulic pressure to open and close the d e. Steam, however, is objectionable ordinarily as an operating medium for the die when casting under relatively high pressure for the reason that it, being of an elastic nature, will yield within the cylinder under the influence of the pressure within the die and thus permit the die sections to slightly separate during the casting operation. An excessive steam pressure overcoming the influence of the pressure within the die would be impractical in many instances. The use of steam as a medium for operating the die sections is rendered practicable, however, by

employing the means which I show herein for exerting a camming action upon the piston rod subsequent to the closing of the die.

Having thus described my invention I claim:

1. In \a die casting machine a die, fluidpressure means for closing said die, and fluid-pressure means adapted to lock said die closed. ,j

2. Ina die casting machine, a die com-t prising a pair of die sections one of which is movable, fluid-pressure means adapted to move one of said sections into intimate engagement with the other, and fluid-pressure means adapted to lock one of said die sections in engagement with the other.

3. In a die casting machine a die, fluidpressure means for closing said die, and fluid-pressure means adapted to be so operated u on closing said due as to cooperate with the first named fluid-pressure means for locking said die closed.

4. In a die casting machine a die comprising relatively movablev die sections, fluid-pressure means for moving one of said die sections with respect to the other to close said die, and fluid-pressure means adapted to lock said die closed, said second named fluid-pressure means comprising-a cam adapted to so cooperate with the first named fluid-pressure means as to maintain one of said die sections in intimate engagement with the other upon closing said die.

5. In a die casting machine, a die comprising relatively movable die sections, a movable headadapted to carry one of said die sections, fluid-pressure means connected to said head and adapted to be so operated as to move one of said die sections Into intimate engagement with the other, and fluidpressure means adapted to cooperate with the first named fluid-pressure means for retaining one of said die sections in intimate engagement with the other.

6. In a die casting machine a die comprising a pair of relatively movable die sections, a movable head adaptedto carry one of said die sections and move the same with respect to the other die section, a pressure cylinder, a piston rod connected to said head and extendm through said cylinder, said piston rod being adapted for reciprocation with respect to said cylinder to move one of said die sections into and out of engagement with the other of said sections, and fluidpressure means adapted to cooperate with said piston rod to lock one of said die sections in intimate engagement with the other.

7. In a die casting machine a die comprising a pair of relatively movable die sections, a movable head adapted tocarry one of said die sections and move the same with respect to the other die section, a pressure cylinder, a piston rod connected to said head and extending through said cylinder, said piston rod being adapted for reciprocation with respect to said cylinder to'move one of said die sections into and out of engagement with the other of said sections, and fluid-pressure means adapted to cooperate with said piston rod to lock one of said die sections in intimate engagement with the other, the second named fluid-pressure means comprising a cam adapted to engage said piston rod and exert a thrust upon the same in the direction of said die. I

8. In a die casting machine, a die comprising a pair of relatively mov ble diesections, a, pressure cylinder, a pi on rod extending through said cylinder and adapted to cooperate with one of said die sections for moving the same into and out of engagement with the other die section, a guide associatedwith said cylinder, a cam adapted to operate Within said guide, and fluid-pressure means adapted to move said cam into engagement with one end of said piston rod and exert a thrust thereupon in the direction of said die to lock one of said die sections in intimate engagement with the other upon closing said die.

In testimony whereof, I signature to this specification.

GEORGE W. BUNGAY.

have afiixed my 2| 

